I want to create a pattern of assemblies that is definied by an excel file. Is this possible?
Well, there is this:
2017 SOLIDWORKS Help - Pattern Tables
Although the pattern information won't be linked to excel, you can copy and paste it from there.
There is also these:
How can I control a component pattern instance in an assembly using design table ?
Linear Pattern Instance Control in Design Tables
Circular paterns in Design Table
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